Machine for spraying concrete curing compounds



June 5, 1951 c. J. HELTzl-:L 2,555,693

MACHINE FOR SPRAYING CONCRETE CURING COMPOUNDS 2; AT TORNEV;-

June 5, 1951 C. 1 HELTZEL 2,555,693

MACHINE FOR SPRAYING CONCRETE CURING COMPOUNDS June 5, 1951 c. J. HELTZEL MACHINE EoR SPEAYING CONCRETE Guam; coMPouNns Filed Jan. 19, 1946 ts-Sheet 5 INVENTOR C. J. HELTZEL ATTORNEYS Patented June 5, 1951 UNITED STATES PATENT OFFICE MACHINE FOR SPRAYING CONCRETE ICURIN G COMPOUNDS Carl J. Heltzel, Warren, Ohio Application January 19, 1946, Serial No. 642,196

6 Claims. l

The present invention relates to improvements in machine for spraying concrete curing compound and more particularly relates to a machine operable over newly deposited concrete on a 'road under construction whereby a sealing compound is spread completely and uniformly over the entire surface of the concrete to seal the moisture in the concrete so that curing can effectively take place.

The highway commissions of a great many States are .now specifying a liquid concrete curing compound which has the consistency of a varnish and some of them also the color of a varnish. This material is sprayed onto a concrete surface and upon hitting the air becomes tacky and finally hardens, 4forming a film over the entire surface. Prior to the 'use of this curing compound, curing was achieved by spreading straw or matting, or some similar material, and at times maintaining a continuous Spray of water over the surface, thus retaining the moisture as long as possible.

When the curing compounds iirst appeared and were put into use, a pressure tank with a long "nose and a spray nozzle, which had a control valve at the end, was handled by a man who walked over the surface, spraying indiscriminately, and giving a covering. This method of course was haphazard, some parts of the surface 'receiving excessive compound and other parts receiving little or none.

As a result the States gradually adopted specifications requiring a certain amount of material per square foot, and requiring that it be evenly applied.

One of the first machines for accomplishing this was the most obvious, by more or less copying an asphalt distributor utilizing a long tube with holes or spray nozzles located evenly across its width and mounting this tube on a carriage of some type which could either be drawn by manpower or "by mechanical means, and locating a pump or if necessary a gravity feed for keeping a constant supply of material into the pipe, it was possible to distribute `the material.

There are several obvious faults with this machine. In the first place, not all holes or spray jets would receive the same pressure, those closest the source of supply, receiving the maximum amount and those farthest away, the minimum. This could be controlled by using dilferent size spray nozzles, thus tending to equalize the pressure. This in turn gives an uneven `spray`1'3'attern and the biggest difficulty of all, 'was the consistency of the material, which as mentioned before is a tacky substance similar to varnish. The multitude of spray nozzles required become easily clogged, gummed up and unworkable, 4so that unless the condition is immediately discovered, considerable slab is traversed before a correction lcan be made.

Another fault is the speed of the machine. Because there is complete coverage across the slab at one time, and a constant flow of material, it is necessary to run the machine intermittently. waiting until the paving operations have progressed, down the slab a suitable distance, then running the spray machine with curing compound. This machine runs considerably faster than the paving operations, thus it frequently stops and waits. This stopping-starting again gives two faults. We encounter the clogging of the jets or spray nozzles as mentioned before and at the same time we do not apply the curing compound at the ideal time.

As an example assume that the paving operation proceeds at a rate of 50 feet per minute (the operation is much slower than this) and assume that a spray machine travels at feet Iper minute, or twice as fast as the paving operations, then the spray machine is idle half of the time, and if the spray machine waits until the paver advances a distance, for instance 500 feet, before starting to spray the `curing compound on the slab, allowing the proper time to elapse for the application, the first part of the spraying operations would be on the concrete after it had set too long. The center of the spraying operations, or half the distance to be traversed, would be applied at the ideal time. As the spraying machine nears the end of its run, in catching up to the paver, it would be applying the curing material too soon after the concrete was poured. In this connection the various States have run tests and each has specified the time that should elapse between the pouring of the slab and the application of the curing compound.

Therefore the ideal arrangement is to have the curing compound applicator or spraying device travel at the same `speed as the paving operations, giving a continuous pour or spraying of curing compound on the slab during the complete operating cycle during the day.

It is an object of the invention to provide an improved machine whereby this ideal arrangement can be accomplished and at the `same time imparting a uniform application of materialen the slab.

With the foregoing and other objects in view the invention will be fully described hereinafter and more fully pointed out in the appended claims.

In the drawings, in which like parts are denoted by the same reference characters throughout the several views,

Figures 1-4 inclusive are diagrammatic views showing the spray pattern laid by the improved machine;

Figure 5 is a top plan view of a machine constructed in accordance with the present invention;

'Figure 6 is a side elevation of the same;

Figure 7 is a fragmentary front elevation of Figure 12 is a perspective View of the carrier and track.

, Referring more particularly to the drawings, 2B designates a carriage adapted to span the roadway under construction and supported for movement on the wheels 2| which ride upon the side forms 22.

The carriage may be driven by a motor or engine or other power supply means 23 installed thereon having the drive shaft 24 driving through a worm or other reduction gear 25 to the transverse shaft or axle 25 of the forward wheels 2i.

Through a lateral shaft 2l the engine may drive a pump 28 connected at its inlet with a tank or reservoir 29 for containing the liquid curing compound. The discharge of the pump 28 is connected by a conduit 32 to the spray nozzle 3l shown in Figure 8 as being contained in a hood 32. A part or all of the conduit may be flexible in order to follow the spray nozzle 3| and hood 32 as the same is given a reciprocating movement back and forth across the front portion of the carriage. For this purpose the hood is supported by brackets 33 from a carrier plate 34. The plate has mounted therein a number of studs 35 and 36, conveniently four, on which are journaled grooved wheels 3l! and 33 spaced rearwardly from the carrier plate 34 by appropriate spacing sleeves 39 and 42.

The grooved wheels 37 and 38 run upon the upper and lower edges respectively of a track bar 4l supported forwardly of the front of the carriage by the extension arms 42 and 43.

Inthe plate is a vertically elongated slot 44- occupied by a headed pin 45, the head of which is of greater diameter than the width of the slot 44 and lies upon the cuter `portion of the plate 34. This pin is affixed to an endless chain 46 trained over and supported by sprockets 4'! and 48 mounted upon the end portions of the track bar 4|. The chain is driven by a drive sprocket 49 mounted at the forward end of the machine drive shaft 24.

In operation, the carriage 20 is driven forwardly by the engine 23 through the axle 26 and the forward wheels 2l. At the same time the pump 28 may be controllably driven to supply the liquid curing compound from the tank 29 to the nozzle 3l. The nozzle moves back and forth over the carrier plate 4I which is Set transversely of the roadway.

lThe endless chain 46 is continuously driven from the engine and the pin is carried along lby the chain 45 passing over the outsides of the sprockets 4l and 48 as it moves from one run of the chain 46 to the other run. When the pin 45 moves from the upper chain run to the lower chain run it will move down in the slot 44 of the carrier plate 34 and at the other end of the chain 46 when the pin 45 moves about the sprocket 48 from the lower to the upper chain run it will ascend in the slot 44.

Thus the spray nozzle 3l is given both a forward movement by reason of the forward progress of the carriage 2li and at the same time a traversing movement back and forth across the center portion of the machine and transversely of the roadway. This compound movement is very desirable in achieving the new and improved spray pattern illustrated in Figures l to 4 inclusive.

Figure 1 shows the course of the rst lateral pass of the spray nozzle 3l across the machine, it being assumed that the machine is moving downwardly of the sheet. During this pass of the spray nozzle 3l from one side form to the opposite side form, the carriage or machine 20 has moved forward a distance equal to half the width of the path of the spray. Thus on the rst lateral pass an area of the concrete road is covered which is enclosed by the numbers I, 2, 3 and 4. The travel mechanism on the carriage thenreverses itself while the machine continuously moves forward on the side forms 22. The second pass covers an area enclosed by the numbers 2, 5, 3 and 4, as shown in Figure 2. It will be noted that the area enclosed within the numbers 2, 3 and 4 has been double sprayed and also that the point 2 is the position of the front or foremost part of the spray at the beginning of the first pass and is at the rear of the spray path at the end of the second pass.

Again the transverse spraying device reverses itself and starts on the third pass, as shown in Figure 3, while the machine is still moving continuously forward. This next pass sprays the area enclosed in figures 2, 5, 4 and 'l and double sprays the area enclosed in the figures 2', 5, 4. There has now been double sprayed the totalV area enclosed in the areas 2, 5, 3 and 4. It will also be noted that the line 2, 4 is the front of the rst pass which passes directly diagonally through the center of the second pass and is the back line of the third pass.

This operation continues down to the end of the slab, giving a completely double spray pattern over the entire area with the exception of the first triangle and a similar triangle at the very end of the slab. Therefore in starting a machine of this type it is desirable to place the machine so that the front end of the spraying pattern is located at the point 2 progressing down the line to the point 4. Thus a little of the spray material or curing compound would be lost at the beginning of the slab and a similar amount at the end of the slab, but the entire slab would be uniformly covered with the curing compound.

It will be appreciated that according to this method there is assured a substantially perfect coverage, and the contractor is assured of economical distribution of his materials, while adhering to the specifications.

It will also be appreciated that the improved machine can be completely synchronized with the speed of the paving operations, thus insuring that the curing compound is applied to the slab at the ideal time, and this proper application is for every foot of slab poured.

Another point of economics is that inasmuch as the machine moves slowly and is synchronized with the paving operations, little or no attention is required compared with previous units where thelatter traveled so fast that it became necessary to stop and start during the entire days pour or operations.

The pin 44 may have a roller thereon if desired in'order to minimize friction.

For various widths of slab to be treated by curing compound, the track 4| may be lengthened out and the sprockets 41 and 48 merely moved out a greater distance to the edge of the road on each side. For this purpose Figures 9 and 10 show the track lll sectional with the sections bolted together for the inclusion of extension sections therebetween. A longer or shorter chain 4B would have to be used.

The hood 32 is held rigidly in place by the brackets 33, thus being held rigidly in place at a predetermined height from the road, keeping air currents away from the sprayed material, protecting it from the weather, thus insuring a uniform distribution of the material over the concrete surface.

The spray nozzle will preferably be located directly in the center of the spray hood and is fastened in place at the top of the hood in any suitable manner, it being coupled to the flexible hose which delivers the curing compound from the pump. The spray hood may be built to any size that will accommodate a spray pattern of preselected width. From a practical standpoint, a ilat spray is the most desirable as to the economy of surface coverage and curing compound gallonage.

The speed of the carrier on the transverse track will be coordinated with the forward motion of the entire machine. The forward speed of the entire machine may be dependent upon the width the spray hood and travel carrier should cover 10 feet in width while the machine is moving forward half the width of the spray hood, or 6 inches. Thus the lateral carrier should travel times as fast as the forward motion of the machine. If however the width of the spray hood is doubled, making it 2 feet, then the ratio becomes 10 to 1 instead of 20 to 1. In any event the speed ratio between the two is a matter of experiment and practice with the various types of compound to be used.

In the claims the term power supply means refers to the motor or engine 23, the rst connecting means refers to the transmission of power from the power supply means 23 to the axle '26 and the wheels 2 I the second connecting means refers to the transmission of power from the power supply means 23 to the extension shaft 24a, sprocket 49 and chain 45, and the integrating means, refers to the reduction gear 25 by which the shafts 26 and '24a are driven at desired relative speeds for producing the double overlapping pattern as shown in Figures 1 to 4 inclusive.

Itis obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims. i

What I claim is:

1. In a machine for applying curing compound to concrete slabs, a wheeled carriage adapted to travel on the side forms of a road under construction, a transverse track supported by said carriage, a carrier movable back and forth laterally of the slab on said track, a spray device supported by said carrier, means to supply said spray device with curing compound, power supply means carried by said machine, a rst connecting means connected to said power supply means for driving the carriage forwardly over the slab of concrete, a second connecting means connected to said power supply means for driving said sprayer transversely of the carriage over the slab, and integrating means carried by said carriage between said first connecting means and said second connecting means for driving said sprayer in timed relation to the forward motion of said wheeled carriage for spraying a double overlapping pattern of curing compound upon the concrete slab.

2. In a machine for applying curing compound to concrete slabs as claimed in claim 1 characterized by the fact that the spray device is at in a direction longitudinally of the slab and at Substantially right angles to the direction of transverse movement of the carrier, and further comprising a hood enveloping said spray device substantially conical and of a diameter slightly larger than the width of the spray pattern delivered by said iiat spray device.

3. A machine as claimed in claim 1 wherein said power supply means is an engine on the carriage for driving both said rst connecting means and said second connecting means, and wherein said means to supply said spray device with curing compound is an engine driven pump the intake side of which is connected to a tank of curing compound carried by said wheel carriage and the discharge side of which is connected to said spray device.

4. A machine as claimed in claim 1 wherein said carrier is driven by an endless chain moving over sprockets, said sprockets being mounted on said transverse track and a pin fixed to the outside surface of said chain for travelling on the outside of said sprockets from one horizontal run of the chain to the other, said pin being movably engaged with said carrier.

5. A machine as claimed in claim 1 wherein said carrier is a slotted plate having grooved rollers projecting therefrom and fitted to run upon both upper and lower edges of said. transverse track with a pin for driving said carrier plate projecting through the slot thereof and being connected at one of its ends to an endless chain roved about sprockets carried at opposite ends of said transverse track, said pin being movable back and forth in said slot.

6. A machine as claimed in claim 1 further comprising chain drive means carried by said transverse track for driving said spray device consisting of two free sprockets at adjacent opposite ends of said carrier and a third drive sprocket between said free sprockets, said drive sprocket being connected to said second connecting means for driving an endless chain passing over said free sprockets for moving said sprayer in both transverse and vertical directions constituting said reciprocating movement.

CARL J. HELTZEL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,929,896 Merritt et al Oct. 10, 1933 1,956,220 Johnson Apr. 24, 1934 2,026,678 Hefner Jan. 7, 1936 2,246,502 Bramsen et al June 24, 1941 2,293,881 Bailey Aug. 25, 1942 .2,367,594 Madison Jan. 16, 1945 

